The subject matter disclosed herein generally relates to rotors for aircraft use. More specifically, the subject disclosure relates to tilting rotors for helicopters or other rotorcraft.
In helicopters or other rotorcraft, a rotor assembly has an axis of rotation, and a plurality of radially extending rotor blades rotating in a plane of rotation. This plane of rotation is nominally perpendicular to the axis of rotation. In some rotorcraft, and under certain operating conditions, it is desired to tilt the plane of rotation so it is no longer perpendicular to the axis of rotation. Rotor assemblies with this capability are often called gimbal rotors and are used in both conventional helicopter applications as a main rotor or as a rotor/propeller in a tilt wing or tilt rotor vertical takeoff and landing (VTOL) aircraft.
To minimize coriolis forces acting on rotating tilted rotor assemblies, a constant velocity joint is utilized to connect the rotor shaft to the rotor assembly to allow the rotor to tilt while maintaining a constant rotational velocity. Previous configurations of such constant velocity joints are complex and have a large envelope and typically increase system weight significantly.